Explain difference with SchemaStore (#11)

Fixes: #10
Signed-off-by: Juan Cruz Viotti <jv@jviotti.com>

README.markdown

@@ -9,6 +9,26 @@ schemas.
 
 [**Visit Sourcemeta Schemas**](https://schemas.sourcemeta.com)
 
+How is this different from SchemaStore?
+---------------------------------------
+
+- **We only ingest official schemas from upstream sources**. While SchemaStore
+  let's community members contribute their own unofficial schemas, those are
+  often not of high quality and tend to deviate over time
+
+- **We cover more than just file formats**. While SchemaStore focuses on
+  singular schemas for common file formats, we also cover ontologies and other
+  kinds of more advanced schema collections
+
+- **We guarantee high JSON Schema compliance**. Compared to SchemaStore, this
+  project is maintained by a member of the JSON Schema Technical Steering
+  Committee, and we pay a lot of attention to spec-compliance in terms of the
+  schemas we ingest and the API layer we provide around them
+
+- **You can self-host your own schema registry! (coming soon)** You can use the
+  same micro-service we use to power this site to create your own internal
+  schema registries, with the schemas of your choosing
+
 Adding Schemas
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